The railway vehicle wheels are subjected to large alternating stress in operation, a crack may be formed therein, and this may cause a safety hazard, thus, the wheels should be ultrasonic detected regularly. In recent years, a kind of ultrasonic flaw detection equipment adapted for detecting flaw without demounting wheels is developed, that is, the wheel is not disassembled, and when detecting flaw, the wheels can be normally installed on the vehicle. The basic form of this kind of flaw detection equipment is that vehicles are parked on the special steel rails for aerial rail bridge; a flaw detection machine rail which is parallel to steel rails is provided in the trench under the rail bridge; the flaw detection machine is slidable along the rail and can stop at the bottom of each vehicle wheel; then the jacking frame of flaw detection machine is lifted, so that the wheel is lifted away from the steel rail, and the wheel is rotated, then felloe probe manipulator on the jacking frame detects the felloe; then the vertical rail on jacking frame is further lifted, and the tread probe manipulator on the jacking frame leads ultrasonic probe holder to abut against the wheel, in order to detects the flaw of the wheels.
The lifting of jacking frame and vertical guide rail of the traditional flaw detection machine for rail vehicle wheel is a serial movement (the vertical guide rail is provided on the jacking frame, and the vertical guide rail is lifted along with the jacking frame), the height of the vertical guide rail is correlated with the height of the top wheel frame, in the narrow space at the bottom of the wheel, this relationship between the vertical guide rail and the jacking frame causes that the tread probe manipulator can not be moved vertical to the steel rail from one side of the wheel to the other side above the top wheel frame, and in order to realize the detection on the wheel, the manipulator must carry on complicated movement, the operation is very complicated and time-consuming, and the efficiency is lower. In the actual operation, this kind of tread probe manipulator is easy to collide with machinery on the bottom of vehicles, and at the same time, it cannot be used on some kinds of vehicles, these serious defects are not suitable for high-speed railway, which may be of high tempo and have different types of vehicles. Therefore, a high efficiency flaw detection machine which is suitable for detecting flaw without demounting wheels is needed.